update on symbol lookup

hi there,

Here is some status update on the work currently done on the symbol lookup.
The basic classes for symbol lookup are in place, and the parser class has
been modified to declare symbols as they are parsed. Specifically, the
SymbolLookup module provides a set of 'Symbol' types and a set of 'Scope'
classes [*]. The details are encapsulated behind a 'SymbolLookup::Table' facade,
which allows some polymorphism for example to support a variety of dialects
(at least C as well as C++ symbol lookup).

The 'dump-symbols' applet that is compiled within the build tree on request
can be used to test the current state of affairs. Note that no analysis is
performed yet as to whether a symbol is just declared or really defined.
That will be the next step. Also, the lookup isn't implemented yet.

However, the basic design is shaped out and so the next steps are relatively
straight forward.

As always, any help is very much appreciated. For details please visit the
synopsis task manager at http://synopsis.fresco.org/issues/task , in particular
http://synopsis.fresco.org/issues/task25 .

Regards,
		Stefan

[*] The diagram at http://synopsis.fresco.org/cxx-parser.png may serve to
     illustrate the high level design